The enzymology and regulation of neutrophil oxidative enzymes will be studied, with particular emphasis on several plasma membrane-associated components. In particular, we will study two enzyme systems: (1) the activatable NADPH-oxidase which is responsible for the superoxide generation of the oxidative burst, and which functions normally in bacterial killing by neutrophils, and (2) a newly discovered NADH-ferricyanide reductase of unknown function. The former is likely to consist minimally flavoprotein plus the recently discovered cytochrome b558. The prosthetic group of the latter is unknown. Defects in the components of the oxidase produce the inherited chronic granulomatous disease, while inappropriate activation of the system participates in the tissue damage seen in a variety of inflamatory diseases (e.g. shock lung, rheumatoid arthritis). Techniques for the study of these enzymes will include UV-visible absorbance spectrophotometry, liquid helium-temperature EPR (electron paramagnetic resonance), stopped flow spectrophotometry, and kinetic approaches.